planing ribbon mahogany

[falconfc]

hey guys

i just bought 2 large boards of mahogany and one turns out to be ribbon mahogany.

i think thats what it is, it has grain strips going in the opposite direction every inch or so.

its a great find but, i am new to this and just bought my first 2 hand plans (veritas 4 1/2, and low angle jack)

and just learning how to use them and all of the sudden this wild grain is through out my second board

and i need advice in how to approach this with my hand planes and scrapers.

what planes, and how to use them, and what angle blades do i use?

thanks

[Bob Rozaieski]

I hate saying that the solution is another tool, because in most cases, it's not the tool that is the problem but how the tool is being used (i.e. not sharp enough, not planing with the grain, bad technique, etc.). But in this case, I think the planes you currently have are going to make it hard for you. I've worked with a lot of ribbon mahogany and it's just not an easy wood to plane with a large, wide smoother, because of the constant reversing grain.

The angle of the blade isn't going to matter much. Any common pitch plane (i.e. 45 degree cutting angle, regardless of plane type) or higher angle will work. The problem isn't anything that can be solved by another blade or angle with your current smoother or jack plane. You just need to plane in the direction of the grain. This might mean planing the stripes in opposite directions. However, this might prove difficult with a 4½ sized plane.

This is my major beef with long, wide smoothing planes. They're a kind of double edged sword in a sense. The long, wide smoothers like the 4½ are fantastic for very well behaved, straight grained, wide panels. But as soon as you get into a board with some reversing grain, that wide blade and long sole begin to cause trouble because it's difficult to selectively plane different areas in different directions with such a large plane.

Smooth planes were historically shorter and narrower than what we tend to prefer now. Take a look at the standard Clark & Williams smooth plane (which is accurately based on 18th century examples). The plane is 6-5/8" long with a 1-5/8" iron. That's almost half the size of a 4½. It's actually just a little smaller than a Stanley #2, and about the size of a typical block plane.

I have a theory about the small size these old smoothers were historically. I think it's because they were used more for taming localized areas of difficult grain, not for planing an entire board or panel. The try/jointer plane would handle smoothing large boards and panels to a satisfactory degree during the flattening process, so smooth planes didn't need to be large enough to plane the entire panel. Instead, it was beneficial to have one that was small enough to just take a few swipes on an area of tough grain.

So I have a couple of suggestions for you. If you don't have a smaller plane (like a block plane), and you don't want to get one, you can try making the iron in that 4½ atom splitting sharp, setting it for the finest cut you can get, and planing across the grain until you've removed all the tearout. Then finish sand the board with some 220 grit.

Alternatively, you can get the same benefit of the older smaller smoothers by using a much smaller plane to tackle the tough spots of reversing grain. Try setting up a block plane with a cambered iron like you would on a smoother and planing each of the stripes in the proper direction. The smaller, narrower plane will make localized planing easier to control and see. Alternatively, if you don't have a block plane (or if you don't want to camber the iron in the one you have) you can use a card scraper and scrape in the proper direction of each stripe. Whichever solution you choose, you need to go in the direction of the grain. Going against the grain is going to cause tearout no matter what tool, blade or angle you use.

[RenaissanceWW]

I have to agree with Bob above that a small "smoothing" plane will help you to tackle each spot independently. However, I have worked quite a bit of ribbon Mahogany using my Veritas BU smoother with a 50 degree blade and it polished it nice and smooth. That being said, the ribbon stuff can vary so widely that your board may just be ornery and preventing that. Your best bet is still to attack it locally with a very sharp smoothing plane.

[falconfc]

my low angle jack takes a toothed blade and a 50 degree blade, will the tooth help get the stock flatter and then i can attack it with my block plane or smoother witch ever works better

[Bob Rozaieski]

Toothing will help to flatten the panel without tearout. Once you switch to the smooth plane or block plane after toothing, make sure you only plane to the bottom of the toothing or you will start to tear out again if you are going against the grain. I'd go with the block plane and and plane the ribbons in the proper direction.

[falconfc]

thanks guys for all the advice.

im ordering a tooth blade this weekend and then will slowly bring it flat.

[adamking]

Scraper planes work well with ribbon mahogany. You'll have to do some extra sanding after, but it makes a difference and really keeps tearout from occurring. At least in my experience.

[Eli]

Hi,

Get the board close to flat going across the grain (it sounds like that's the plan with the toothing plane). The 4 1/2 should be good enough. Make sure the blade is very sharp, and move the frog forward, closing the mouth. If you can increase the blade angle, it will help, too. Skewing the plane (holding it at an angle) helps with tear-out and also makes the cut thinner, so you can avoid crossing into another ribbon. After the plane, a scraper can get you where you need to be.

Even when cleaning up the toothing, dont' be afraid to attack the board from different angles. A sharp plane will give you a fair cut even cross-grain.

Eli